Guides

How Much Mulch Do I Need?

Quick Answer

To estimate mulch, multiply area in square feet by depth in feet. Divide cubic feet by 27 for cubic yards, or divide by bag size for bag count.

Practical Guide

Mulch quantity depends on two things: the size of the bed and the depth you want to install. A shallow refresh needs much less material than a new bed.

Measure the length and width of rectangular areas, or split curved beds into smaller sections. Add the sections together before converting depth from inches to feet.

Mulch Formula

Area square feet x depth feet = cubic feet. Cubic feet / 27 = cubic yards. For bags, divide cubic feet by the bag volume listed on the package.

Example: 180 square feet at 3 inches deep is 180 x 0.25 = 45 cubic feet. That is 1.67 cubic yards, or about 23 two-cubic-foot bags before extra material.

Depth Planning

Use 2 inches for a light refresh, 3 inches for standard weed control, and 4 inches for heavier coverage in a new area. Keep mulch several inches away from tree trunks and plant stems.

Common mulch depth choices
DepthBest forPlanning note
2 inchesLight refreshGood when an older mulch layer is still present.
3 inchesStandard bedsA common depth for weed control and moisture retention.
4 inchesNew bedsUse carefully around plants to avoid burying crowns.

FAQ

How many cubic feet are in a cubic yard of mulch?+

One cubic yard contains 27 cubic feet. Divide cubic feet by 27 to convert to cubic yards.

How many bags of mulch are in one cubic yard?+

A cubic yard equals about 14 bags if each bag is 2 cubic feet, or 9 bags if each bag is 3 cubic feet.

Is 2 inches of mulch enough?+

Two inches is often enough for a light refresh, but 3 inches is more common for weed suppression in open beds.

Should mulch touch tree trunks?+

No. Keep mulch pulled back from trunks and stems to reduce moisture problems and bark damage.